Railway draft appliance



Oct. 13, 1964 H. E. VICKERMAN RAILWAY DRAFT APPLIANCE 12 Sheets-Sheet 1 Filed May 27, 1963 INVENTOR AL E. V/CKERMAN III" ATTORNEYS Oct. 13, 1964 H. E. VICKERMAN 3,152,699

RAILWAY DRAFT APPLIANCE Filed May 27, 1963 Y 12 Sheets-Sheet 2 a; q w l v w m a q I N A m I Q v IUHIIUI I 'L. y 66 64 flz'f. 3.

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INVENTOR HAL E. VICKERMAN flndrus i Star/e L Affoawevs Oct. 13, 1964 H. E. VICKERMAN I 3,152,699

RAILWAY DRAFT APPLIANCE Filed May 27, 1963 12 Sheets-Sheet 3 r INVENTOR. HAL E. VIcKERMAN qndrus Stark AfroRuEYs Oct. 13, 1964 H. E. VICKERMAN 3,152,699

RAILWAY DRAFT APPLIANCE Filed May 27, 1963 12 Sheets-Sheet 5 fiiq. 10.

INYENTOR 2 HAL E. V/CKERMAN find/us Star/e Ammvevs T Oct. 13, 1964 H. E. VICKERMAN RAILWAY DRAFT APPLIANCE l2 Sheets-Sheet 6 Filed May 27, 1963 INVENTOR L E. VICKERMAN AWORNEYS Oct. 13, 1964 Filed May 27, 1963 H. E. VICKERMAN RAILWAY DRAFT APPLIANCE 12 Sheets-Sheet 7 fit .16.

BY 71n I I INVENTOI HAL E. VICKERMAN drus StarKe Oct. 13, 1964 H. E. VICKERMAN 3,152,699

RAILWAY DRAFT APPLIANCE Filed May 27, 1965 12 Sheets-Sheet 8 HAL E. VICKERMAN vndrusiStarlge &

Arromvevs Oct. 13, 1964 H. E. VICKERMAN 3,152,699

RAILWAY DRAFT APPLIANCE Filed May 27, 1963 12 Sheets-Sheet 1O A j INVENTOR r HAL E. VICKERMAN 0t) 4 R, a BY i o ndrus Sfa'rlge Q 7, Amnusvs Oct. 13, 1964 Filed May 27, 1965 H. E. VlCKERMAN 3,152,699

RAILWAY DRAFT APPLIANCE HUI l2 Sheets-Sheet 11 yqndrus iStarKg ATTORNEYS Oct. 13, 1964 Filed May 27, 1963 H. E. VICKERMAN RAILWAY DRAFT APPLIANCE 12 Sheets-Sheet 12 INVENTOR. HAL E. VICKERMAN jqndrus stamz A'f-fonuEvs 3,152,699 RAILWAY DRAFT APPLEANQE HaliE. Vickerrnan, Milwaukee, Wis, assignor to A. O.

This invention relates to a draft appliance of a railway car .and'more particularly relates to, a draft appliance haviug a self-contained or unitary construction.

Railway cars andfreight cars in particular are subjected to a large number of shock forces during operation. These shock forces are imposed on the couplers at the ends of the car and are either in buff or draft, a buff force being one which is directed inwardly against the coupler while a draft forceis directed oppositely thereto or outwardly of the coupler.

Normally, ,theshockforces of the greatest severity occur in buff and resultfromthe practice of coupling cars to one another by effecting a heavy sudden impact between cars to enable their couplers to engage and automatically interlock. Thus, for example, when assembling cars to form a train, individual cars maybe rolled down a. suitable incline toward a standing car or line of cars of the train to effect coupling.

The coupling of the cars may also be effected by bumping the cars together 'by means ofa prime mover or engine. These coupling forces attain very substantial proportions and are capable of causing severe damage to the car, its couplers, and the car contents, if any.

Other, though normally less substantial buff forces as well as draft forces occur in and between the cars which are part of a moving'train. These forces are due in part to the fact that a certain amount of slack motion is provided in the car couplers. During starting and acceleration of the prime mover or engine of the train and during leaving a curve and on entering an up grade, the individual cars of the train tend to stretch apart and each car is subjected to a heavy jerk or draft force'by the faster 'traveling'car immediately ahead of it the instant the slack ears of the train bunch 'or crowd together and each car is subjected to a bulf force by the faster moving car to its 7 rear when the slack is taken out of their couplers. In this case, the magnitude of the force increases progressively from the rear to the front of the train.

The present invention isdirected to a draft appliance which is fully capable of taking up and absorbing shock forces imposed on a coupler of a railway car and more specifically is directed to a draft appliance in which the component parts thereof are arranged and interconnected to form a self-contained assembly adapted to be mounted within a railway car center sill in supporting relation with the coupler.

In accordance with the invention, the proposed draft appliance is comprised of a coupler receiver assembly adapted to be connected to a coupler of a car, a two-way acting'shock absorberconnected to the coupler receiver assembly for absorbing forces imposed on, the coupler, and a resilient return means connected to the coupler receiver assembly and urging the latter and the shock absorber unit to normally neutral positions. The coupler receiver assembly includes a housing formed with longi tudinally spaced external abutment surfaces and which are adapted to engage similarly spaced abutmentsurfaces United States Patent ice formed within a center sill of a railway car to secure the housing longitudinally of the sill. A coupler adapter block is mounted for forward and rearward sliding movement relatively of the housing and has means to receive a car coupler and means adapted to be releasably connected with the coupler tosupport the same longitudinally of the sill. The block and housing are formed with 1ongitudinally spaced stop surfaces cooperating to limit forward and rearward movement of the block in thehousing and which serve to take up and transmit any unabsorbed portion of a couplerforcefdirectlyinto the sill.

In accordance with a preferred construction, the coupler block is provided with replaceable wear plates on pre-' selected of its surfaces and similar Wear'plates areprovided on the corresponding surfaces of the housing and sill to provide slide surfaces for the block which are replaceable. The plates desirably have a high wear resistant characteristic-to reduce frictional wearing therein.

The shock absorber in a preferred form of the invention consists of a hydraulic piston-cylinder unit connected through its cylinder member to the inner end of the housing of the coupler receiver assembly. The piston of the hydraulic unit is connected by an operating rod to the coupler adapter block and is opposed forsliding movement in the cylinder to effect damping of coupler forces by the restricted flow or displacement of hydraulic fluid through a number of axial grooves provided in the cylin der. To prevent fluid cavitation in the unit whenthe piston is caused to accelerate rapidly in the cylinderby a heavy, suddenshock force on'the coupler, a fluid return means is secured exteriorly of the cylinder between the opposite ends thereof. The fluid return means is in iiuid communication withthe ends of the cylinder by valved openings which are adapted to be actuated upon a prevention are disposed directly within the pistonto provide direct fluid flow from the high pressure side of the cylinder to the low upon actuation of the relief valves. These valves have a compact construction, a high fluid handling capacity and are quick opening and closing.

Thefluid orificing set forth enables an exceptionally compact construction for the hydraulic unit and is capable of highly efficient and reliable functioning under all load conditions.

Another novel aspect of the invention relates to the connection betweent-he operating rod of the hydraulic unit and the coupler block. This connection is preferably effected by a ball and socket joint to relieve the rodof bending loads as forces are transmitted thereto from the block. In accordance with the invention, the elements of the joint are vertically slidably assembled in a recess in the coupler block and the recessis shouldered to retain the elements to the block so as to'permit the block and rod to be readily slipped apart when it is desired to service the hydraulic unit.

The resilient return means is connected between the housing and coupler adapter block and includes oppositely acting resilient element s yieldingly maintaining the block in an intermediate or neutral slide position in the housing. Upon displacement of the block in either direction from neutral as by a shock force on the appliance, the resilient elements are energized and-upon load release reposition the block in the neutral position. The shock absorber mechanism is automatically repositioned in a corresponding neutral position at the-same time.

It is contemplatedto employ either a single or double a. the coupler receiver assembly or in the alternative a double set of elements mounted one each along the sides of the coupler assembly in outboard relation with the sides of the center sill. In accordance with another aspect of the invention, the resilient elements are mounted on elongated rods which are telescopically extensible and retractable. The telescopic form of the rods enables .a highly compact overall construction for the resilient return means and is particularly advantageous where it is desired to mount the return means on the underside of the coupler receiver assembly in applications wherein only a limited space is available thereat due to the configuration of the railway car.

The proposed unitary draft appliance of the invention is secured longitudinally of the center sill of the car solely by means of the abutments formed in the housing of the coupler receiver assembly and in the sill itself. Vertical support is provided by means of brackets attached across the bottom of the sill beneath the housing of the coupler receiver assembly and the hydraulic shock absorber unit by mounting bolts. The bracket may be formed as an integral part of the appliance or as separate and distinct members as desired. The various parts of the appliance are otherwise free of attachment to the sill and are designed and arranged to permit the appliance to be installed within or removed from the sill without presenting any interference thereto. Maintenance, repair, and/ or replacement procedures are greatly simplified and facilitated by this construction.

With the present construction, the sill within which the appliance is mounted is in no way subject to wear from friction during operation due to the self-contained form of the coupler receiver assembly. Further, the problem of frictional wear in the proposed appliance is largely alleviated due to the utilization of the wear plates on those parts which are slidable with respect to one another. The present construction is of further important advantage in that any unabsorbed portion of a coupler force is transmitted into the sill of the car via the coupler block and the fixed housing, thus avoiding direct impact between the sill and related parts of the coupler and appliance and precluding objectionable brinelling, coining, swaging and the like of the sill. Moreover, in

the present construction, built in mechanical stops are provided for limiting coupler block sliding movement when subjected to buff and draft shock forces and hence the range of such movement can be controlled by the appliance manufacturer.

When the draft appliance is to be used with a long shank coupler, the coupler receiver assembly is modified in construction to meet added code and industry requirements for the long shank coupler. For example, by code such couplers are required to be supported vertically intermediate the ends to reduce the moment arm in the coupler for downwardly directed loads. This is achieved in the present invention by modifying the front of the coupler block to include a deck-like support platform within which is resiliently mounted a vertically reciprocal hearing plate. The deck is designed such that with a coupler attached to the block, the bearing plate engages and supports the coupler adjacent the front end of the latter.

In some applications, it is desired that the long shank coupler be centered automatically in the sill when free of connection with the couplers of other cars to facilitate coupling of the cars. For this purpose, it is proposed. to

incorporate a spherical bearing assembly in the coupler block to seat the rear end of the coupler and which includes a rocker member movable as a unit with the coupler with horizontal swing movement thereof. The rocker member is normally urged to a centered position in the coupler block and the coupler to a centered position in the sill by a pair of resilient elements contacting the member on either side of center. These elements are selectively energized as the coupler swings to either side of center and act on the rocker member to return the with another coupler.

Other objects and advantages of the present invention will appear in the course of the detailed description of the invention appearing hereinafter.

The accompanying drawings illustrate the best mode presently contemplated of carrying out the invention.

In the drawings:

FIG. 1 is a plan view of a portion of a draft appliance embodying the present invention in operative relation within the center sill of a railway car, some parts being broken away and others being shown in section;

FIG. 1a is a view taken on line 1a1a of FIG. 1;

FIG. 2 is a vertical axial section of the draft appliance of FIG. 1, certain parts being shown in elevation;

FIG. 3 is a view of the front end of the draft appliance taken on the lines 3-3 of FIG. 1, with parts of the retaining structure for the draft key being broken away and others sectioned for clarity of illustration;

FIG. 4 is an enlarged fragmentary side elevation of the draft key retaining structure taken along the lines i-4 of FIG. 3.

FIG. 5 is a horizontal sectional view of the front end of the draft appliance shown in FIG. 1 illustrating the parts in a full pull out position;

FIG. 6 is similar to FIG. 5 illustrating the parts in a fully inward position;

FIG. 7 is a vertical axial sectional view on an enlarged scale of a hydraulic piston-cylinder unit embodied in the present draft appliance with the piston shown in a neutral position within the cylinder in the full lines and at the limits of buff and draft movement in the phantom lines, certain parts being shown in elevation and other being broken away;

FIG. 8 is a vertical transverse sectional view of the piston-cylinder unit taken along the lines 83 of FIG. 7;

FIG. 9 is a view similar to FIG. 8 only taken on the lines 99 of FIG. 7;

FIG. 10 is similar to FIGS. 7 and 8 only on a reduced scale and taken on the lines 1[illti of FIG. 7;

FIG. 11 is a vertical axial section of a fluid volume compensator which is attached to the hydraulic pistoncylinder unit of the appliance;

FIG. 12 is a perspective view of an end portion of a railway car center sill having a standard construction;

FIG. 13 is a perspective view of the portion of the sill shown in FIG. 12 modified to receive a separate cast extension to render the sill suitable for receiving the draft appliance of the invention;

FIG. 14 is an axial vertical sectional view of a modifled form of the draft appliance of the invention with a part of a sill and a coupler being shown in phantom to illustrate the general relationship of the parts to one another;

FIG. 15 is a plan view of the draft appliance shown in FIG. 14 with some parts being broken away and others being sectioned;

FIG. 16 is a side elevation of the draft appliance shown in FIGS. 14 and 15 with the sill and coupler being omitted;

FIG. 17 is an elevational view of the front of the modifled draft appliance taken on the lines 17-17 of FIG. 14;

FIG. 18 is an elevational view of the rear of the modified draft appliance taken on the lines 18-18 of FIG. 1

FIG. 19 is a fragmentary vertical sectional view of a modified form of the draft appliance shown in FIGS. 1 to 11, illustrating an alternative arrangement and construction of the return spring assembly;

FIG. 20 is a front end elevation-a1 view of the structure shown in FIG. 19;

FIG. 21 is a rear end elevational view of the structure of FIG. 19;

FIG. 22 is a fragmentary vertical axial view, partly in section and partly in elevation, of a modified form of the draft appliance shown in FIGS. '14- to 18, illustrating an.

' alternative construction for the return spring assembly;-

and

FIG; 23'is-a front end elevational view of the structure of FIG. 22.

The formofthe invention illustrated in FIGS. 1 to 11 oftherdrawings isdesigned for use with railway cars of from 50 to 60 feet in length and which are equipped with the A.A.R. standard E type coupler as opposed to the longshank AiAsR; alternate standard E type coupler and:;the: A.A;R. standard F type coupler which are used on cars exceeding :60 feet in length. Referringrrnore particularly toFIGS. .l'to 4, the unitary draft appliance 1 of-the invention is shown operatively disposed within a railway carcenter sill 2, which extends longitudinally and shock. It will be understood that a second draft appliance andcouplerareslmilarly disposed in the other extremity of the center sill at the opposed end of the railway car;

The illustrated draft appliance 1 is formed generally of I a self-contained coupler receiver assembly 8 connected to coupler '7 to suppontthe samein sill 2, a two-way acting hydraulic shock absorber 9 connected to the inner end of coupler receiver assembly 3 for effecting dissipation of shock forces imposed on coupler '7' and'couplerreceiver assembly 8, and a return-spring assembly it connected to coupler receiver assembly Sin outboard relation with the opposed sides 3 of sill 2 and urging the coupler assembly and the shock absorber unit to neutral positions.

Coupler receiver assembly 8 includes a channel-section housing member 11 disposed longitudinally of the sill in upwardly opening relation thereto. The side walls 12 of 1 housing 11 are ofiset inwardly immediately adjacent the forwardmost. end of the sill 2,,and define a pair of external vertical abutments 13 at the rear edge thereof. Rearwardly, housing member If is closed by a heavy gauge i openstopped end wall 14 the rear face of whichdefines a rear vertical abutment l5 spanning the housing ll. The portion of sill 2 receiving housing ii is formed to comprovided with a correspondingly widened interior portion extending from housing end wall 14 to a. point just to the rear, of the aforedescribed external abutment 13 to accommodate enlargement 23. Block enlargement 23pmvides on its front face a pair of vertically extending stop surfaces 24 which are adapted to engage the complenientary shaped vertically extending abutment or stop surfaces 2d formed intcriorly of housing 11 at the front of the enlarged or widened portion thereof to thus limit forward movement of the block in the housing 11. Similarly, the rear face 26 of block enlargement 2 3 cooper-ates with the front face 27 of the housing end wall 14 which forms a vertically extending abutmentor stop surface to limit rearward movement of the block in housing 11.

For purposes of maintaining the block in proper sliding engagement with housing and to reduce the problem-of wearing inthe block and the corresponding surfaces of.

the. housing andsill from'the effects of friction, the present invention contemplates providing the bottom and top.

surfaces of block 22 with the relatively thin wear plates.

28and'29 respectively. Plates Zdand 29 are preferably composed of-steel alloy or other suitable metal having a high wear resistance characteristic. Similar wear plates 2% and 29' are secured to the inside of the housing bottom wall 3%? and to the inside of sill top wall 5 respectively and cooperate with the corresponding plates 23 and 29-to take up frictional wear from the surfaces which they cover. it has been found thatfrictional wear in the sides of the blocs and the corresponding sides of housing 11 is negligible, accordingly, these surfaces are not provided with wear plates. 7

Wearplate 28 is preferably secured to housing wall 30 by a number of locater pins 31provided interiorly of the wall and which register with and fit within suitable open:

ings in the plate to enable the ready replacement of the plate when worn. In addition, wear plate 28 is preferably symmetrically formed and locater pins 31 are disposed to permit plate 28 to be reversed and/or inverted with respect to the housing if locally worn, thus increas-.

ing the life of the plate. The other of the wear plates 28, 29 and 29 may be secured as by welding or the like andwhen worn are cut off and replaced. The provision of wear plates on the aforementioned surfaces enables block 22 to be maintained in close sliding engagement within housing llv forlong periods of operation as well as permitting ready, inexpensive means for renewmg contacting surfaces when worn to. a predetermined plement the outer configuration thereof with a front and rear abutment surface 16 and 17 respectively provided within each sill side wall 3 in direct engagement with the corresponding abutment 13 and 15 of housing 11 to thus releasably secure the housing longitudinally of the sill 2.

' As most clearly shown .in FIGS; 1, 2 and 4, housing ill is supported vertically within sill 2 by a bracket 18 extending between and secured to the opposed flanges 4 of sill side walls 3 as by a number of mounting bolts 19. A number ofshims Zll'are interposed between the ends of bracket 18 and the flanged edges 4, as in the illustrated construction, the housing extends below the level of the sill. As willbe more fully described hereinafter, an additional bracket 21 is similarly secured to sill flanges l beneathhydraulic unit 9 to support the rear of the appli ance vertically-in sill 2.

Coupler reeciver assembly 8 further includes an elongated coupler adapter block 22 mounted for sliding movement longitudinally of housinglll. The front of block 22 projects from thehousing and sill through open end 6' and as will be more fully explained hereinafter receives and connects to coupler 7'through the front end to support the coupler for sliding. movement in the sill. In

order to limit block movement in the housing and in turn limit coupler movement inthe sill when subjected to a bud or draft force, the rear end of block- 22 is widened or offset laterally as indicated at 23 and the housing is extent.

Referring now to the mounting of coupler 7 in'coupler block 22, the latter is provided with a generally rectangular longitudinally extending chamber 32 opening at the front of the block. The opposed sides of chamber 32 are each formed with an inwardly extending, horizontal kaye guide 33 having the slots 34 to support a transverse draft key 35. The slot 34 in the right-hand key guide 33 as viewed in FIG. 3 is extendedvall the way through to the corresponding right-hand side of block 22 to perkey 35 to be inserted within and removed from the key. guides through the blockproper. The slot 34- in the left-hand key guide 33 has a blind construction save for a'knock out opening 36, the purpose of which con-. struction will appear.

Coupler '7 is formed with the coupler jaws 37 adapted to interlock with the coupler of another car and has an elongated, tapered shank 38 which is provided with a transverse slot 39 at the end opposite jaws 3'7. Coupler shank 38 extends rearwardly within the chamber 32 in coupler block 22 with slot 3'9 receiving draft key '35 held I in lceyguides 33 to thus connect the coupler to the block.

ably assembled in the right-hand slot 34 in overlying relation with the upper right-hand end of key 35 as viewed in FIG. 3 to hold key 35 in positive seated relation against shoulder 40. The exterior right side of coupler block 22 is grooved from the top of the block to a point just above the corresponding right-hand slot 34, as shown in FIG. 4, to form a ledge-like projection 42 in the side of the block. A locking pin 43 is inserted vertically through portion 42 and through the outer end of the retainer plate 41 as shown to hold the latter firmly against draft key 35, thus releasably securing the draft key between the coupler block and coupler. A cotter key 44 is inserted through locking pin 43 immediately below plate 41 to hold the pin in place.

To remove draft key 35 from block 22, cotter key 44 is initially withdrawn and first locking pin 43 and then retainer plate 411. are removed. Draft key 35 is then pried up to clear the shoulder 40 by any suitable lever, such as a screw driver. Then, working from the left-hand side of the block 22, a suitable pin, not shown, is inserted through knock out opening 36 and the draft key 35 is driven out of the coupler block 22 by a hammer or other suitable means. This removal procedure may be performed quite readily, enabling the coupler 7 to be rapidly disconnected from block 22 as may be required for purposes of replacement of a broken or damaged coupler. The reinsertion of draft key 35 within block 22 to reconnect a new coupler thereto is also a relatively fast, simple procedure with the construction of the present invention.

Coupler 7 and coupler adapter block 22 are designed and constructed to permit coupler 7 to pivot through a limited arc with respect to coupler block 22 and in both the horizontal and vertical as the car with which the appliance is being employed traverses a curve or grade in the track. For this purpose, coupler slot 39' is formed somewhat wider and deeper vertically than draft key 35. Additionally, the rear edge 45 of shank slot 39 is formed with a convex surface contour which engages the corresponding rear edge 46 of draft key 35 when coupler 7 is pulled fully forwardly in block 22 under application of a draft force to accommodate pivotal movement of coupler 7 in the full pull out position. This position of the parts is shown in FIG. of the drawings.

if1 the fully inward position of coupler 7 in block 22, as shown in FIG. 6, the rearend of the coupler shank 38 is in abutment with the rear end wall 47 of chamber 32 in coupler block 22, and the front edge 48 of shank slot 39 is spaced from the corresponding front edge 49 of draft key35, this relationship resulting by making the distance between shank front and rear surfaces 48 and 45 respectively less the width of the draft key35 greater than the distance from the rear end of coupler shank 38 to chamber end wall 4'7 with coupler 7 in full pull-out position. Thus positioned, coupler 7 may pivot on chamber rear end wall 47.

In addition to the above measures, a limited clearance is provided between coupler shank 38 and key guides 33. A similar but much greater clearance is also provided between the front end of shank 3S and the sides of chamber 32 at the front end thereof to accommodate pivotal movement of the coupler in the block.

As best viewed in FIG- 2, coupler 7 is supported for horizontal swing motion in block 22 by a raised shoulder Stl formed integrally with block 22 at the entrance to chamber 32. A wear plate 51 is positioned on shoulder 549 to prevent rapid wearing of the supporting surface.

Referring again to FIG. 6 of the drawings, coupler block 22 is shown in the rearmost slide position relative to housing 11, this position being fixed by stop surfaces 26 and 27 formed on block 22 and housing 11 respectively as previously described. In this position, coupler jaws 37 are spaced forwardly of the end of center sill 2, thus precluding objectionable coining, swaging and the like of the sill when the parts are forced fully inwardly under bulf loads on the coupler.

The hydraulic shock absorber mechanism 9 which is attached to the inner end of coupler receiver assembly 8 for dissipating coupler forces is shown herein as a piston-cylinder assembly. See FIG. 2. The attachment of mechanism to coupler receiver assembly 8 is effected between housing rear end wall 14 and the cylinder 52 of the assembly 9. To this end, the wall 14 is provided with a central aperture 53 which is counterhored as shown in FIGS. 1 and 7 to form an arcuate retaining shoulder 54 partially surrounding the aperture 53. Cylinder 52 is disposed within aperture 53 in endwise abutting relation with shoulder 54 and is secured to wall 14 as by a weld laid between the contiguous surfaces of the cylinder and wall.

A piston 55 having an associated operating rod 56 is mounted for sliding movement in cylinder 52 between the cylinder front and rear heads 57 and 53 respectively. Operating rod 56 extends through cylinder front head 57, with suitable bearing support and packing provided in the head to seal the rod thereto, and is attached at its front end to the rear of coupler adapter block 22, thereby connecting the shock absorber unit 9 to the block. The attachment is preferably effected through a ball-andsocket joint to enable the block and rod to float or pivot universally with respect to one another in the event of any longitudinal misalignment therebetween to relieve the rod of bending loads from coupler forces transmitted thereto from the block 22. In the present invention, the balland-socket connection is of single surface construction being designed to permit adjustment between rod 56 and block 22 in the buff direction of loading only, and as will now be described, is fashioned in a manner enabling convenient and rapid disassembly of the rod from the block. The front end of rod 56 is threadably connected to a ball or knuckle 59 formed over its front face with a segmental spherical convex surface contour. A dowel pin 60 is provided to prevent knuckle 59 from working loose on the rod 56. The rear end of coupler block 22 is provided with a vertically extending recess 61 opening to the bottom and rear of block 22 and having a constricting lip or shoulder 62 formed on the periphery of the rear opening portion thereof. Knuckle 5d is adapted to fit upwardly within recess 61 and is releasably held therein by shoulder 62. The ball joint further includes a knuckle socket 63 formed complementary to the front face of knuckle 59 and releasably held in recess 61 in bearing relation with knuckle 59 by a coil spring 64 which is disposed in a horizontal opening 65 extending through the rear of the block 22 and opening at the front face of chamber end wall 47 previously described. Spring 64 is adjustably held in compression by a set screw 66 disposed in the opening 65 which is properly tapped therefor.

With the above construction and with appliance 1 removed from sill 2 and coupler 7 withdrawn from block 22 to detach operating rod 56 from block 22; it is only necessary to loosen set screw 66 working through the front end of block 22, and then slip knuckle 59 out through the bottom of recess 61. With rod 56 free of block 22;, the rod 56, piston 55, and cylinder front head 57 are removable ,as a unit from cylinder 52 to enable servicing of hydraulic unit 9, the head 57 being secured in place as by a snap ring-groove arrangement.

In order to prevent dust and other foreign material from collecting on operating rod 56 and entering within and possibly interfering with the operation of hydraulic unit 9, rod 56 is enclosed between cylinder 52 and block 22 by a flexible boot and clamp assembly 67. Assembly 67 includes a flexible, bellows-like dust boot 68 disposed concentrically of rod 56. The front end of boot 6?} is clamped to rod 56 just to the rear of adapter block 22 by a screw tensioned clamp ring 69, as clearly shown in FIGS. 1 and 2, While rearwardly dust boot 68 encircles an annular shoulder 70011 front cylinder head 57 and is secured thereto by a'secondscrew tensioned clamp ring -69;

Referring again to the construction ofthe hydraulic unit 9 and more specifically to the "meansby which conplerforces are dissipated, it will be' understood that cylinder SZ is filled with a=-suitable hydraulic fluid medium. The fluidis adapted to be restrictively displaced in cylinder '52 in response to 'piston movement therein in either .a' forward or rearward direction through a series. of axially extending, 'circumferentially spaced grooves 71 providedwithin the cylinder and being longer than the longitudinal extent of piston 55. In the illustrated construction; the grooves 71'are shown terminating attheir front end in a common radial plane which is spaced from the cylinder' 'fronthead57 and'have a varying axial length "with the "longest of the grooves terminating in spaced relation from rear cylinder head 58. Piston 55 is sealed to the cylinder 52by a circumferentially extending seal .ring72 located intermediate a'pair of piston wear rings '73..3I1dli5 normally positioned in cylinder 52 so'that itv 1 1ovetlies grooves '71 and with its front face lying in the 7 common radial plane of the. grooves with seal'ring 72 to the rear'thereof as 'shown in'FlG. This'position'of force causing the:piston. to slide rearwardly. in cylinder 52. The aggregate cross-sectional area of grooves71 available for fluid displacement is greatest at the outset of. piston movement and decreases progressively as piston 55 slides rearwardlyinthe cylinder owing to the aforesaid construction of grooves71. At the same time, howi ever, the initialforce on hydraulic unit 9 drops off graduallyadue' to the fluid opposition to piston movement. In accordance'with the invention, the grooves '71. are arrangedlsuch that the CYOSSrSCCtlOIlEl area thereof "decreases .at a rate which results :in.a.substantially uniform pressure'within.the hydraulic unit. or .as close thereto as rea- ,sonably,..possible. over the: major .portion of its buff. stroke fonagiven coupler force or range offorces. .of this constructionlthe.hydraulicPunitQ is. capable .of dis- -As.a result sipating' extremelyheavytbuff forces ina highly e'fiicient .and reliable manner.

With piston .55 in neutrallposition andcausedtoslide forwardly within. cylinder 52:.as by a draft. force oncoupier. 7, the total. cross-sectional area of; grooves 71 is avail- .able forfluid displacementaand remainsavailable until piston ring 72 reaches the front. terminus of the grooves toleffect the desired damping of the force. 1

,The rearward oraforward movement of piston .55 in cylinder .52 corresponds to rearward-or forward move- .ment of block 22inHhousing l1. .The-.previously described systemof mechanical stops. between block .22 and housing 11..is designed to, prevent, piston .55. from moving p vrearwardly within cylinder. 52 past the positionshown in 'the right-hand phantom lines in FIG. 7. 1the..piston.55 is spacedfromcylinder rear head 58,..thus preventing the piston from bottomingout in the cylinder In this position,

and causing severe injury .thereto. Similarly, in the case of forward movement .of the piston, v.thelstop surfaces. of

block 22 and housing 11 preclude piston movement beyond the position indicated inthe .leftthand phantom lines ofFlGI7 :in which position piston 55 is spaced from cylinder front head,57.

necessary to clearly describe the feature of the present I invention. For a more detailed description, reference .is made to a copending patent application of Charles 0.

Breitsprecher, entitled Relief Valve, Serial No. 131,391, filed August 14, 1961.

Valves "74 and 75 are of identical construction and operation andeaccordingly, for purposes of simplification,

in the piston 55. A cylindrical valve member 78 is slidably disposed in valve body 76 and is formed at its front end and which corresponds to the low pressure side of the valve with a frustoconically shaped-valve head 79 seating against a ring 80, the ring being of beveled construction to define with the valve head 7% an annular fluid confining chamber 81. Valve member 3 is normally held seated on the ringed by a coil spring 32 assembled coaxially of the member 78 in an annulus'fo'rmed between the latter and valve body 76. Valve head 79 is provided with a series of fairly large generally radially outwardly extending openings 83 establishing fluid communication between chamber 81 and the high pressure side member 78 is designed so that the effective area in annu lar chamber '81 is slightly greater than that between openings 83. Consequently, a given fluid pressure in cylinder 152 on the high pressure side of the relief valve results in and effective force tending to force valve body 78 off ring 80 to open the relief valve. Normally, however, the valve body ismaintained closed by coil spring 82. At some pressure level, however, and which is set to correspond to the maximum fluid pressure desired in hydraulic unit 9 in the buff direction of its stroke in the case of valves 74, the net effective force tending to unseat valve .body '78 will exceed the bias force of springSZ at which time the valve body will begin to open. As soon as valve -member"78 .cracks open, the effective pressure responsive area of the frusto-conical valve head 79 increases rapidly;

' adding to the effective valve opening force and enabling Topreclude excessively; high sfluid pressures in hy- .draulic unit 9and resultantdamage theretoupon a particularly severe draft or bulf force on coupler 7, a pressurereliefsystem is provided .in the unit. In the illuswtrated constructiom this system is in the form of a. pair of buff relief valves [4 and a single-.draftrelief valve '75 "mounted directly in'piston 5 5. A preferred valve coni struction is shown and hereinafter described to the extent valve member "78 to rapidly fully open when the fluid pressure rises to the preselected valve.

In order to insure against any possible opening of the valve responsive to fluid pressure on the low pressure side thereof, valve head '79 is further provided with a number of passages 84 opening into annular chamber 31 between valve member 78 and valve body 7d from the low pressure side of the relief valve. Fluid is thus free to enter the chamber 81 and acts against an external shoulder 85 formedzon valve member 78 to retain the latter tightly against ring 89. The pressure responsive area of shoulder '85 exceeds that of the face of valve head 79 exposed to the lower pressure side .of the relief valve. to provide this result. a

If in operation the force on the draft appliance is sufficiently great to result in the fiuid pressure in hydraulic unit9 reaching the predetermined setting of either the relief valves 74 or 75, the correspondingrelief valveior valves open and permit rapid fluid displacement from the high pressure side of the :piston andcylinder to .thelow pressure side to relieve the pressure and prevent further pressure build-up. The relief valve or valves close when the hydraulic unit is in the full. buff or draft position or at such times in the stroke of the unit when the pressure drops below the valve settings.

The location of the relief valves 74 and 75 directly in the piston enables a direct flow of fluid between the high and low pressure sides thereof and more importantly enable an unencumbered construction within the hydraulic unit. Valves of the illustrated type are particularly well suited for the present invention because of their compact design and more importantly because of their quick opening action and high fluid handling capacity.

In order to prevent fluid cavitation in hydraulic unit 9 when piston 55 is caused to accelerate rapidly in cylinder 52 as by a particularly severe shock force on coupler 7, the hydraulic unit further includes a channel-section fluid return member 86 secured to cylinder 52 in lngitudinally extending upwardly opening relation. As most clearly shown in FIGS. 8-10, member 86 corresponds generally in width to the inside width of sill 2 to the rear of sill abutment 17 and is divided into the separate longitudinal half-sections 87 by cylinder 52. The sides 88 of the fluid return member 86 are secured in fluid tight relation to cylinder 52 as by a weld laid the length of their adjacent surfaces. The bottom wall 89 of member '86 is in the plane of and abuts against the bottom wall 30 of housing 11 as shown in FIG. 7 and is secured thereto as by welding. At the front end of the fluid return member 86 and referring now to FIGS. 7 and 8, there is provided a pair of fillet-like end plates 90 welded to cylinder 52 and to the sides 88 and bottom 89 of the member 86 to seal the front end of the latter to the cylinder. In a similar fashion, a second pair of fillet-like plates 91 are provided at the rear end of member 86 and are'welded to cylinder 52 to seal the rear end of the member thereto (see FIGS. 7 and 10). The front end of member 85 is in direct two-way fluid communication with the front end of cylinder 52 through means of a pair of static fluid orifices 92 provided in either side of cylinder 52 just to the rear of front head 57. Orifices 92 extend radially outwardly to each of the split sections 87 of mern her 86. A similar pair of static fluid orifices 93 is provided in the rear end of cylinder 52 to establish two-way entially extending groove 94 and is sealed to the cylinder 52 by a pair of seal rings 95, one to each side of the groove. Groove 94 is in fluid communication with the fluid return member 86 through a pair of orifices'96 lo-' cated in the lower half of cylinder 52 one to either side of center, and which open into each side 87 of member 86. Cylinder front head 57 is further provided with a valved recess 97 in its rear face and which is in fluid communication with groove 94 through an orifice 98. Recess 97 is closed by a check valve 99 located in a suitable annular groove provided in the rear face of head 57 as shown and which is secured to head 57 by a threaded pin 100. Check valve 99 includes a valve seat 101 mounted on pin 100 and Which is resiliently urged against the head to normally close recess 97 to fluid passage by a coil spring 102 assembled co-axially of pin 100. A spring bearing plate 103 is mounted on pin 100 at the headed end thereof to seat the spring 102. With valve seat 101 lifted off cylinder front head 57, fluid communication is established between fluid return member 86 and cylinder 52 by way of orifices 96, groove 94, orifice 9t; and recess 97.

Referring now to the rear end of the cylinder, a fluid volume compensator 195 which is welded to and encloses the rear head end 58 of cylinder 52 as will be more fully described hereinafter. An annular groove 106 is disposed on the circumferential surface of head 58 and a drilled opening 107 is extended diametrically therethrough.

As best shown in EEG. l0, groove 106 is in fluid communication with the split segments 87 of fluid return member 86 by a pair of radial orifices 10S. Drilled opening 107 in'turn is in fluid communication with the cylinder 52 to fluidly connect the fluid return 86 to cylinder 52 by a valved opening 109 in cylinder rear head 58. Opening 109 is normally closed to fluid flow by a check valve 99' which is substantially identical in construction and functioning to previously described check valve 99. In the case of check valve 99', however, retainerrpin is threadably secured within the end of fluid volume compensator 105. To prevent interference between the pin 100' and piston 55 when the latter is in a rear slide position in cylinder 52, the rear face of the piston is provided with a central recess 110 as shown.

Oheck valves 99 and 99' are urged toward the closed position by the combined force of their respective springs 102 and 102' and the hydraulic fluid in the cylinder acting on the inner face of their respective valve seats 101 and 101.

The valves 99 and 99' are urged toward the open position vby the hydraulic fluid in fluid return member 86 acting on the outer face of the respective valve seats 101 and 101 through the aforedescribed system of orifices, grooves, etc. The faces of the valve seats 101 and 101' and the 'flexure characteristic of spring elements 102 and 102 are designed such that when the fluid pressure in cylinder 52 substantially equal that in fluid return member 86, valves 99 and 99' are held in the closed position and when the fluid pressure in cylinder 52 drops a predetermined level below the pressure in fluid return member 86, valves 99 and 99' are selectively caused to open.

The operation of the aforesaid static fluid orifices 92 and 93 and check valves 99 and 99' will now be described to illustrate the manner in which fluid return member 86 functions to prevent fluid cavitation in cylinder 52. For purposes of explanation it will be assumed that piston 55 when in a forward slide position in cylinder 52 is caused to accelerate rapidly rearwardly within cylinder 52 in response to a heavy buff force on coupler 7. It will be further assumed that the pressure differential between the front and rear ends of the cylinder at the outset of piston movement is of sufficient disparity that fluid cannot enter the front of the cylinder 52 through grooves 71 and through front static orifices 92 via fluid return member 86 and rear static orifices 93 fast enough to prevent cavitation within the front end of cylinder 52. When this happens, the pressure within the front of cylinder 52 drops below that within fluid return member 86 and as a result thereof, the net effective force tending to open check valve 99 increases. When the pressure differential reaches the predetermined level, check valve 99 opens allowing fluid to surge into the front end of cylinder 52 from fluid return member 86 in suflicient quantity to re-establish a continuous fluid condition therein. The setting of valve 99 is such that the above action occurs before any appreciable cavitation takes place in the cylinder and in this manner then, fluid cavitation in cylinder 52 with rearward movement of piston 55 therein is prevented. The rear check valve 99 acts in a similar manner to safeguard against fluid cavitation in the rear of cylinder 52 during forward sliding movement of piston 55.

In a piston type hydraulic system including the illustrated embodiment of the present invention, piston movement in the cylinder varies the length of the piston rod which is in the cylinder, thus varying the total available volume in the cylinder for the hydraulic fluid. Then too, the fluid in the system tends to change volume due to fluctuations in fluid temperature. The various metal parts of the system in contact with the fluid also tend to expand or contract as their temperature varies. In accordance with the present invention, such factors are compensated for and a completely filled fluid system is obtained without risk of high static fluid pressures, by the fluid volume compensator 105, shown in FIGS. 1, 2, 7 and 11. compensator includes a generally cupshapedbody 111 formed at its open end with a surround- "ing'flange 112. The connection of the compensator 105 to therear head 58 Of'cylinder-SZ is effected in any suitable manner. As shown head 58 is formed with a flange 114 which mates with and is secured to flange 112 of compensator :body 111bya screw tensioned split clamp *ringi115. Head58 and body 111 form a housing which slidably receives a cup-shaped piston 116. An axially rearwardly extending pin 117 is secured to piston 116 in [the center thereof and is slidably received within a tube or collar 118.formed integrally with the compensator Ibody 111 to support the piston for sliding movement in the compensator 105.

. Piston 116 is normally constrained'toward a forward spaced from the sides of the compensator body 111 as ton from the hydraulic'fluid system. Diaphragrn120 has a main body portion 121 of circular ,design and is formed with a doubled-over marginal portion 122 ex "tending normally ofthe plane .of body portion 121 and whiohterminates in a wedge-shaped edge 123. The diaphragm fits overthe front of-piston 116 with marginal portion 122 'projectingor disposed within the clearance between the piston 116 and compensatorbody 111. The

wedge-shaped marginal edge 123 of diaphragm 120 is "clamped within a complementary formed annular recess 124 defined by complementing annular grooves-in the opposedand mating edges of .body 111 and head 58, thus .sealing the frontof the compensator fromthe rear or piston conveying end thereof and providing a variable volume for hydraulic fluid in the compensator. Fluid communication between the front end of the compensator 105 andthe hydraulic fluid system including the cylinder '52 and.fluid return member .86 ofthe hydraulic unit 9 isestablished by providing head 58 with a passage 125 leading to drilled opening 107. The fluid connection is completed to cylinder 52 from passage 125 and drilled opening 107 by groove'106 and passage 108, fiuid return memberfid and orifices 93' in the rear end of the cylinder 52 previously described.

In this manner, the cylinder 52 and fluid return member 86 are fluidly connected with the variable fluid volume sourcepresented by compensator .105 to provide automatic adjustment forchanges in the eifective available volume inthe cylinder .and fluid return member for the fluid aswell as changes in the total volumeof fluid occurringin operation.

Referring .now to the details of construction .of return spring assembly 10, a pair of opposed compression spring elements consisting of a buff spring. 126 and a.

draft spring 127 are. mounted longitudinally of the coupler receiver'assembly 3 and hydraulic unit 9 in outboard relation .along .each sill. side Wall 3 by an elongated rod 128. The front end of each rod 128 is con- .nected to a front spring support bracket129 secured across the bottom of coupler block 22. at the frontend thereof, the bracket extending outwardly and clear of the'sill proper in the assembly position of draftappliance as appears in'FIG. l. The front end of rods 128 is Welded'to a bearing plate 131 registering withand removably secured to a corresponding flange 131 on the outer ends of bracket 129jby a number of nut and bolt assemblies.

Buff springs 126 are mounted coaxially of each of 'rodsl128 and are secured to bearing plate 131} at their An intermediate spring. support bracket 132 is secured across the bottom of housing 11 of coupler receiver assembly 8 approximately in line with. housing rear end wall 14. The ends .of bracket .132 are in longitudinal alignment with the ends of front bracket129 and as clearly shown in FIG; 3

have an outwardly opening C-like construction through which the rods 128 extend. A centrally apertured spring hearing disc or washer 133-is slidingly received on the rods 128 immediately rearwardly of the intermediate brackets 132 and is resiliently held in backing engagement therewith by draft springs 127 to seat the rear ends of buff springs 126. a 1

Draft springs 127 are mounted concentrically of each of the rods 128 at-the' rear ends thereof andengage washer133 at the frontends. Rearwardly, draft springs 127 are seated by a'washer and stop disc assembly 134 carried on the rear bracket155 secured across the bottom of fluid return member 86 of hydraulic unit 9. Assembly 134 comprises a stop disc 136 rigidly connected to The ends of rear bracket 135 are apertured to accommodate sliding movement of the rods 128 therethrough. Secured to the ends of bracket 135 and forming a forward extension thereof is a tubular spring seat 138 having an apcrtured end wall 139 slidingly receiving the rods 123 and dimensioned to pass stop disc 136 butnot washer 137.

In accordance with the invention, the draft springs-127 have greater flexure characteristic than buff springs126 and normally hold bearing Washer 133 intermediate bracket 132 and bearing washer 137 in engagement'with end wall'139 of spring seat 138 against the opposed bias of buff spring 126 when the coupler and draft appliance are in an unloaded condition. Additionally, the-springs 126 and 127 are of a length such that when assembled being positioned'well forwardly within cylinder 52 in the neutral position previously alluded to and described in connection with the hydraulic unit. Thus positioned, the. block 22 and piston '55 have a relatively long stroke in the buff direction of movement, this being desirable due to the greater magnitude of the buff forces under normal conditions of operation.

The functioning of return spring assembly 10 is as follows. 'Assurning initially that th coupler 7 is 'subjected to a buff force, forcing coupler block 22 to slide rearwardly in housing "11 from neutral position. Initial rearward movement of block 22 causes the preloaded buff springs 126 to initially further compress against washer 133 as front bracket 129 slides rearwardly with the block,

the washer 133 initially remaining seated on intermediatebracket 132 inasmuch as the draft springs are stronger than the buff springs. Rods-128 and stop discs 136's1ide rearwardlywith respect to rear bracket 135 with rearward sliding movement of block 22 while bearing washer 137 is fixed with respect thereto as it engages spring guide end wall 139, thus effecting the desired compression in buff springs 126. As block 22 continues rearwardly to further compress buff springs 126, the buflf and .draft springs eventually reach an equilibrium condition with respect to each other. At such time, washer'133 lifts off intermediate bracket 132 andboth springs 126 and 127 undergo compression with rearward movement of block22. When the force which is causing the'coupler block to slide rearwardly in housing 11 is selectedfrom coupler 7,'buff and draft springs 126 and 127 return to their initialprecompressed condition tothereby return block 22'to its initial or neutral position in housing 11 through their combined spring force. This in turn results in a corresponding return of piston 55 to its neutral position in the cylinder 52. r

In the case of a draft load on coupler 7, coupler block is v 22 slides relatively forwardly in housing 11 from its normal position therein, causing the rods 128 to move forwardly. Stop discs 136 force bearing washers 137 forwardly against draft springs 127 with rod movement to compress the springs against washer 133 of the intermediate bracket 132. When the draft force is relieved y from coupler 7, draft springs l27 extend to their original and sill in the installation and removal of the draft sill appliance. This feature greatly facilitates and shortens -'the time to effect installation and removal of the appliance.

Further and referring particularly to FIGS. 2 to 4, the return spring assembly is designed and constructed such that it is disposed in a horizontal plane below the plane of draft key 35 and in no way hinders or interferes with the removal and insertion of the key in the block in replacing a broken or damaged coupler. In this connection too, it will be noted that the front end of the coupler block 22 is recessed along the sides and that with the block in its normal position in housing 11, the lock pin 43 and retainer plate 41 holding draft key 35 in block 22 and exposedalong the side of the latter as is the knock-out opening 36. This construction allows pin 43 and plate 41 to be readily removed and inserted when the block is in its normal slide position in housing 11. As a result of this design and further due to the fact that the spring assembly is in no way interconnected with the draft key, the draft appliance may be left completely intact during replacement of a broken or damaged coupler. A highly simple and fast method is thus provided by the present construction for replacing a defective coupler.

The overall operation of the draft appliance of the invention will now be described in connection with various different operations and conditions which it may experionce when installed on a railroad car.

Assuming in the first instance that a car equipped with a draft appliance of the invention is part of a line of cars'which is to be started from a stationary position and that the prime mover of the train is initially backed up to take out slack from between the cars and then driven rapidly forwardly to rapidly accelerate the individual cars. As the train backs up and slack is taken from the car under consideration, coupler '7 and coupler block 22 slide rearwardly until the rear stop face 26 of coupler block 22 engage the corresponding stop face 27 of housing 11, after which the rearward force is transmitted directly to the sill and car. The piston 55 is caused to slide rearwardly in cylinder 52 during the initial backup period and to the rearmost position therein simultaneously with the above. As a result, the full stroke of the hydraulic unit 9 is now available to absorb and dissipate the shock force on the car in question as it is jerked rapidly forwardly as the prime mover picks up speed. All damaging shock forces are absorbed by the hydraulic unit 9 due to the action of the previously described novel fluid flow system and the car and its lading are thus protected from damage in the starting of the train. Any unabsorbed shock force is transmitted into the sill and car through coupler block 22 and housing 11 via the front stops 24 and 25 of the block and housing respectively. Fluid cavitation in hydraulic unit 9 during the starting of the train is prevented by means of the check valve 99' in cylinderrear head 58, the operation of which has been previously discussed. In addition, the hydraulic unit 9 is protected respect to the impact force.

- construction.

come a serious problem in this respect.

from overload as the car in question attains the speed of the prime mover by draft pressure relief valve 7 5.

Where the train is started without initially removing slack'from the individual cars, only the draft stroke of the hydraulic unit is available to effect the shock dissipation. Under the above conditions, however, the shock force is much less severe and is applied more gradually.

In effecting coupling of railway cars provided with the draft appliance of the invention as by impact therebetween the hydraulic units of the appliances are initially in neutral position and at impact each unit is actuated towards bulf position to effect a shock resisting action with In this case check valve 99 in front cylinder head 57 and the buff pressure relief valves 74 serve to preclude fiuid cavitation and overload in each of the units to assure proper functioning thereof. Rear stops 26 and 27 of coupler block 22 and housing 11 respectively cooperate to transmit any unabsorbed force directly into the sill and car. i

A similar shock resisting action and valve functioning in the hydraulic flow system is provided in the draft appliance of the invention when the car with which it is being used is subjected to bumping and jerking as the train is operated over curves and on grades and is otherwise decelerated and accelerated.

From the above described explanation, it can be seen that the draft appliance of the invention affords the car with which it is associated, a high degree of protection from the various shock loads to which it may be subjected in operation.

The integrated draft appliance of the invention is supported within the sill solely through the bolted brackets 18 and 21 and may be readily removed from and installed within the sill as a result thereof. Repair and maintenance of the appliance is greatly expedited by the present The proposed design further permits the ready replacement of a coupler when required to over- In addition to these and other features, the present invention provides an extremely compact and rugged shock absorbing unit which is well adapted to take up the various forces on railway cars.

preciated that in the sill construction specified herein the extreme end of the sill and more specifically that portion 7 ahead of the rear sill abutmentslS represents a departure from the usual 'sill design. To adapt a standard sill so that it may accept the draft appliance of the invention, and referring now to FIG. 12 illustrating one form of a sill of conventional design, the striker plate 140 of the standard sill 141 is initially removed as by cutting the rivets holding the plate in the sill. Everything is then removed from within the sill 141 including internal lugs, if present, and the pro-existing draft appliance. The sides of the standard sill are then cut away along their front edges in the manner indicated in FIG. 13, leaving the top of the sill intact as shown. A separate hat-section sill extension 14-2 which is preferably a cast construction is fabricated with the requisite offset sides and internal abutment surfaces described earlier and with the edge configuration on the sidesthereof required to mate with the l corresponding cut-away sides of the standard sill previously described. The sill extension 142 is then mated to the cut-away end of the standard sill 141 and secured thereto as by welding. To strengthen and rigidify the sill modified in this manner, sill extension 142 may be 

1. A SELF-CONTAINED DRAFT APPLIANCE FOR MOUNTING WITHIN A DOWNWARDLY OPENING CENTER SILL OF A RAILWAY CAR AND FOR SUPPORTING A COUPLER OF THE CAR WHICH COMPRISES: A HOUSING ADAPTED TO BE FIXEDLY SECURED ADJACENT AN OPEN END OF THE SILL, A COUPLING ADAPTER BLOCK SLIDABLY DISPOSED IN SAID HOUSING, MEANS DISPOSED WITHIN THE CONFINES OF SAID BLOCK TO RELEASABLY RECEIVE A COUPLER, SHOCK ABSORBING MEANS INCLUDING A CYLINDER FORMING AN INWARD EXTENSION OF SAID HOUSING AND A PISTON CONNECTED TO THE INNER END OF SAID COUPLING ADAPTER BLOCK TO ABSORB DRAFT AND BUFF SHOCK FORCES TRANSMITTED TO THE LATTER FROM THE COUPLER, RESILIENT RETURN MEANS CONNECTED BETWEEN SAID ADAPTER BLOCK AND SAID HOUSING AND DISPOSED BENEATH THE LATTER AND URGING SAID BLOCK TO AN INTERMEDIATE NEUTRAL SLIDE POSITION IN SAID HOUSING AND SO THAT SAID PISTON IS DISPOSED BETWEEN THE ENDS OF SAID CYLINDER, STOP MEANS WITHING SAID HOUSING TO LIMIT THE FORCE AND AFT MOVEMENT OF SAID ADAPTER BLOCK, AND MEANS DISPOSED EXTERNALLY OF SAID HOUSING FOR COOPERATING WITH SAID SILL TO PREVENT LONGITUDINAL MOVEMENT OF THE HOUSING RELATIVE TO THE SILL. 